Advertising and other information is often temporarily presented on large sheets which are placed on billboards, truck panels and the like. One form of such sheet material is tensioned vinyl sheet Such sheet may be printed upon and surrounded by a more rigid plastic border which is RF (radio frequency) welded to the sheet. The border typically includes a large bead, circular in cross section, which operates as a tenon in association with a C-shaped mortise associated with a mounting frame.
Mounting frames may take on a plurality of configurations. Of value is the ability to tension the sheet and to maintain it in a tensioned and wrinkle-free state. Mechanisms have been used which first lock the sheet in place and then apply tension through off-center bolts and the like.